Langmuir monolayers and Langmuir-Blodgett (LB) films of the decatungstoeuropate [EU(W5O18)(2)](9-) (EuW10) and the amphiphilic Ir complex I have been successfully fabricated by using the adsorption properties of the EuW10 polyanion dissolved in the aqueous subphase onto a positively charged I monolayer at the air-watcr interface. The compression isotherms and Brewster angle microscopy (BAM) of monolayers of I on pure water (I monolayer) and on a subphase containing 10(-6) M EuW10 and 10(-3) M NaCl (1/EuW10 monolayer) have been studied. Infrared and UV-vis spectroscopy of the transferred LB Films indicate that EuW10 and 1 molecules are incorporated within these LB films. X-ray reflectivity (SXR) and atomic force microscopy (AFM) experiments indicate that LB films of 1 present a heterogeneous morphology while 1/EuW10 Films show a flatter and more homogeneous surface as well as a layered structure with a periodicity of 4.1 nm. Mixed monolayers of 1 and DODA (dimethyldioctadecylammonium bromide) have been prepared with EuW10 polyanions in the subphase to control the concentration of 1 and EuW10 polyanions within the LB films. AFM and SXR experiments with the transferred LB Films show that the dilution Of I with DODA improves the layered structure. The luminescence of I is partially quenched by EuW10 in the 1/EuW10 LB Films, while emission from EuW10 is not detected. On the other hand, emission from both entities is preserved in the LB films prepared from mixed DODA/1 monolayers, in which the red and yellow emissions arise independently from EuW10 and 1, respectively. The different DODAA ratios lead to changes in the emission color. Therefore, they constitute a promising color-tunable luminescent material.